<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<div>
    <input type="text" v-model="n1">
    <input type="text" v-model="n2">
    <input type="button" value="加" @click="f('+')">
    <input type="button" value="减" @click="f('-')">
    <input type="button" value="乘" @click="f('*')">
    <input type="button" value="除" @click="f('/')">
    <h3>结果:{{result}}</h3>
</div>
<script src="js/vue.min.js"></script>
<script>
    let v = new Vue({
        el:"body>div",
        data:{
            result:"",n1:"",n2:""
        },
        methods:{
            f(x){
                //判断输入的内容是否是数字
               if (isNaN(v.n1)||isNaN(v.n2)){
                   v.result="输入错误!";
                   return;
               }
               //eval("xxx") 此方法可以将字符串以JS代码的形式运行
               v.result = eval(v.n1+x+v.n2);

            }
        }
    })
</script>
</body>
</html>